/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.dolphinscheduler.api.k8s;

import org.apache.dolphinscheduler.dao.entity.Cluster;
import org.apache.dolphinscheduler.dao.mapper.ClusterMapper;
import org.apache.dolphinscheduler.remote.exceptions.RemotingException;
import org.apache.dolphinscheduler.service.utils.ClusterConfUtils;

import java.util.Hashtable;
import java.util.Map;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

import io.fabric8.kubernetes.client.Config;
import io.fabric8.kubernetes.client.DefaultKubernetesClient;
import io.fabric8.kubernetes.client.KubernetesClient;

/**
 * use multiple environment feature
 */
@Component
public class K8sManager {

  private static final Logger logger = LoggerFactory.getLogger(K8sManager.class);
  /**
   * cache k8s client
   */
  private static Map<Long, KubernetesClient> clientMap = new Hashtable<>();

  @Autowired
  private ClusterMapper clusterMapper;

  /**
   * get k8s client for api use
   *
   * @param clusterCode
   * @return
   */
  public synchronized KubernetesClient getK8sClient(Long clusterCode) throws RemotingException {
    if (null == clusterCode) {
      return null;
    }

    return getAndUpdateK8sClient(clusterCode, false);
  }

  /**
   * @param clusterCode
   * @return new client if need updated
   */
  public synchronized KubernetesClient getAndUpdateK8sClient(Long clusterCode, boolean update) throws RemotingException {
    if (null == clusterCode) {
      return null;
    }

    if (update) {
      deleteK8sClientInner(clusterCode);
    }

    if (clientMap.containsKey(clusterCode)) {
      return clientMap.get(clusterCode);
    } else {
      createK8sClientInner(clusterCode);
    }
    return clientMap.get(clusterCode);
  }


  private void deleteK8sClientInner(Long clusterCode) {
    if (clusterCode == null) {
      return;
    }
    Cluster cluster = clusterMapper.queryByClusterCode(clusterCode);
    if (cluster == null) {
      return;
    }
    KubernetesClient client = clientMap.get(clusterCode);
    if (client != null) {
      client.close();
    }
  }

  private void createK8sClientInner(Long clusterCode) throws RemotingException {
    Cluster cluster = clusterMapper.queryByClusterCode(clusterCode);
    if (cluster == null) {
      return;
    }

    String k8sConfig = ClusterConfUtils.getK8sConfig(cluster.getConfig());
    if (k8sConfig != null) {
      DefaultKubernetesClient client = null;
      try {
        client = getClient(k8sConfig);
        clientMap.put(clusterCode, client);
      } catch (RemotingException e) {
        logger.error("cluster code ={},fail to get k8s ApiClient:  {}", clusterCode, e.getMessage());
        throw new RemotingException("fail to get k8s ApiClient:" + e.getMessage());
      }
    }
  }

  private DefaultKubernetesClient getClient(String configYaml) throws RemotingException {
    try {
      Config config = Config.fromKubeconfig(configYaml);
      return new DefaultKubernetesClient(config);
    } catch (Exception e) {
      logger.error("fail to get k8s ApiClient", e);
      throw new RemotingException("fail to get k8s ApiClient:" + e.getMessage());
    }
  }

}
